Two Upfront questions: 1) Floating regions? and 2) can we stack elements (text over image)?

Right clicking in Upfront on a region I'm editing shows a Floating Region option. This sounds like a great way to put semiopaque backgrounds beneath text elements or beneath images to highlight them. But when I try to create the floating region they either end up below the region where I can't get to them or they disappear completely. I can't find a single reference to Floating Regions in your Upfront tutorials and since they seem to behave erratically I'm not sure what they are used for.

Second question, is it possible to stack draggable elements in the same region? For example, If I wanted have a text element overlaid over an image element. Is this possible? I tried it and it doesn't seem to work. I'm trying to avoid having to create many many images that are just text on an opaque background.

I've attached one of the dozens of comps the designer provides showing a background image overlaid by an opaque background overlaid by a text element.